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Modified Aisin-Warner AW4 Tech

Root Moose

NAXJA Forum User
Location
ON, Canada
Hopefully another useful thread for the archives/search similar to the NV242 thread. My attempt to give something back to the forum for all the great info I lurk here: consolidated info.

What I know about the AW4:

  • 4 speed automatic, overdrive transmission
  • Ratios: 2.80, 1.53, 1.00, 0.75
  • Strong, reliable tranmission
    • 250,000 mi (400,000 km) between rebuilds not unheard of (!!)
    • Toyota version (A340) lives behind modded turbo 6 cylinder Supras
  • Smaller than GM 700R4/4L60(E)
  • Quite low first gear ratio (2.80:1)
    • GM TH700R4/4L60(E) is 3.06:1
    • GM TH350 is 2.52:1
    • GM TH400 is 2.48:1
    • Jeep/ChryCo TF727 is 2.45:1
  • moderate overdrive/4th ratio (0.75:1)
    • GM 700R4 is 0.7:1
  • Has torque converter clutch
  • Uses standard New Venture (NV; ex-New Process) series transfer case bolt pattern
  • 1989 (inclusive) and earlier are 21 spline output (is this correct?)
  • 1990+ are 23 spline
    • compatible spline count with other t-cases like Dana 300
  • 1996 and earlier variants use a TCU/ECU separate from the engine ECU
  • 1997+ variants use a TCU/ECU that is integrated with the engine ECU

Here is the manual/FSM for the earlier variants of the AW4:


Here is a wiring diagram for a 1989 AW4 (originated from wagoneers.com, linked from my site to save them bandwidth):

AW4Wiring.png

The following links deal with modifying the shifting of the AW4 into a full manual transmission. I guess technically it would be a "semi-automatic" like an old VW Beetle since it doesn't have a clutch.

Anyway, here are the links:


Also, a couple of simpler (yeah, right!), cool mods by NAXJA member "GoJeep":


Please add, correct, modify any of this information as you see appropriate.

r@m
 
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air bags bro.

-Scott
 
Hell, I'm just going by what SeanP told me, this is the first automatic transmission vehicle I've ever owned.......

Sorry for the almost SPOBI!

CRASh
 
CRASH said:
Hell, I'm just going by what SeanP told me, this is the first automatic transmission vehicle I've ever owned.......

Sorry for the almost SPOBI!

CRASh


Almost?????????????

TOTAL SPOBI!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!


hinkley
 
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Beezil said:
sobi?

"spelling optional, brain inactive"

?????

Spilling Out Bull$hit info?
 
Overdrive Ratios

I've heard/read in a few places now that the AW4 used in Jeeps came with two different overdrive ratios: 0.75:1 and 0.70:1.

Does anyone know what years had what ratios?

T!

r@m
 
The 23 spline output trannies have a 0.7 OD, the 0.75 OD is only for 21 spline output.
 
XJoachim said:
The 23 spline output trannies have a 0.7 OD, the 0.75 OD is only for 21 spline output.

Is this correct after 1996 as well? Could've sworn I read my 2001 was 0.75...

If that is correct, that makes another case for running a little more gear in the axles than stockish RPMs with big tires.

r@m
 
Root Moose said:
Is this correct after 1996 as well? Could've sworn I read my 2001 was 0.75...

If that is correct, that makes another case for running a little more gear in the axles than stockish RPMs with big tires.

r@m

other way around......

23 spline are .75.....

I've verifyied this by removing the OD planetary from my parts aw-4, and marking roatation.

21 spline are .705
 
Yep, sorry, mixed them up :doh:
 
Let's keep the tech rollin'. Anybody got the wiring diagram for a 91+ tranny. I kinda need this info really, really soon.
 
SPOBI is right!!!

My 97 FSM says that the air bag controller is under the drivers seat. There is indeed a bracket there with three studs, but not control module. I could not for the life of me figure out what that box was under the center console. The reason I am now bumping up this thread is that I need to fix some of the wires in the air bag plug due to some zealous angle grinding near the area by one of my helpers. (not naming names Billy!)

You would think the FSM would accurately show what is in my vehicle :rolleyes:

SeanP
 
SeanP said:
SPOBI is right!!!

My 97 FSM says that the air bag controller is under the drivers seat. There is indeed a bracket there with three studs, but not control module. I could not for the life of me figure out what that box was under the center console. The reason I am now bumping up this thread is that I need to fix some of the wires in the air bag plug due to some zealous angle grinding near the area by one of my helpers. (not naming names Billy!)

You would think the FSM would accurately show what is in my vehicle :rolleyes:

SeanP
The FSM is partially right: the air bag control module used to be under the seat but it got relocated under a recall (my 98 had it under the seat and I had to take the XJ to the dealership and have them move it). IIRC the issue was that if it got wet it'd short out and release the airbag.
 
Kejtar said:
The FSM is partially right: the air bag control module used to be under the seat but it got relocated under a recall (my 98 had it under the seat and I had to take the XJ to the dealership and have them move it). IIRC the issue was that if it got wet it'd short out and release the airbag.

Yep, that's right. I still need to relocate mine (not gonna spend a half day with the stealership to do it, though, since it's just a couple of bolts).

Nay
 
cool, thanks. We bought the jeep in 98 with 11K miles on it, so it must have already been done. Now if I can just track down this code 45 that the Check Engine is throwing (something to do with the tranny, won't shift from 1st).

SeanP
 
I have a 1990 Cherokee, which has a blown AW4, my friend found a 1998 AW4 for $200.00, I JUMPED at this chance. From what I'm reading, this transmission won't work in a 1990?
 
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